1. Technical Field
The present invention relates to a liquid ejecting apparatus such as an inkjet-type recording device, a display manufacturing apparatus, an electrode forming apparatus, or a biochip manufacturing apparatus and a liquid ejecting head installed in the liquid ejecting apparatus.
2. Related Art
Ink jet printers as liquid ejecting apparatuses appropriate for paper printing are well known. Generally, ink jet printers have a configuration in which a liquid ejecting head having a fine nozzle for ejecting liquid (liquid droplets) is loaded on a carriage reciprocating with respect to printing paper. For example, in a liquid ejecting head disclosed in JP-A-2000-211130, an ink supply needle combined with an external ink cartridge for receiving ink, and a filter for trapping foreign bodies included in the ink is provided at one end of the ink supply needle.
Since the filter can trap air bubbles in the ink in addition to foreign bodies included in the ink, an air bubble generated on the front side of the filter continues to grow with time. In the case that the air bubble grows very large, the air bubble may pass through the filter relatively easily thereby causing inferior ejection, and accordingly, a so-called recovery operation that forcedly discharges the air bubble with the ink regularly or appropriately is required.
For the air bubbles' passing through the filter in the recovery operation, the air bubbles need to be close to the ink supply needle/filter, so that the air bubbles can block a predetermined region of the filter in the ink supply needle. In the case that the filter is not sufficiently blocked, the flowing ink easily passes through the filter, and accordingly, a sufficient pressure (discharge force) cannot be applied to the air bubbles.
However, it is difficult to maintain the above-described status for air bubbles that have been decreased in volume by over a specific amount due to the effect of the surface tension or buoyant force of the ink applied to a boundary face of the air bubbles. In other words, since a sufficient discharge-operation for air bubbles cannot be performed by the recovery operation, there is a problem that inferior discharge is caused or frequent recovery operations are required.